A British museum has been searching for parts of the Lorenz cipher machine, used by the Nazis in World War II to send secret messages.

So when sharp-eyed museum volunteers happened upon what appeared to be a Lorenz teleprinter on eBay, it almost seemed too good to be true.

National Museum of Computing volunteer John Whetter went to Essex to investigate. There, he found “the keyboard being kept, in its original case, on the floor of a shed ‘with rubbish all over it’,” the BBC reports.

“I think it was described as a telegram machine, but we recognised it as a Lorenz teleprinter,” Whetter tells The Guardian. The teleprinter is the portion of the machine that actually transmits the encrypted message.

Wetter tells the BBC that they bought the device for about $14: “We said ‘Thank you very much, how much was it again?’ She said ‘£9.50’, so we said ‘Here’s a £10 note - keep the change!‘”

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Even then, it’s real value wasn’t yet clear. A spokesman for the museum told The Two-Way in an email that at the time of the purchase, “the Lorenz teleprinter was thought to be a relatively common commercial Lorenz teleprinter. Its military origins came to light only when it was being refurbished.”

Its military history was clear when the museum discovered the cleaned-up machine was “complete with swastika detailing and even a special key for the runic Waffen-SS insignia,” the Guardian reported.

According to the museum, the Lorenz cipher was even more complex than the Enigma code used by the Nazis. And British mathematician Bill Tutte is credited with “shortening the war and saving countless lives” when he broke the code. He deduced “the architecture of a Lorenz machine without ever having seen it,” which allowed the Allies to “read German High Command’s top secret messages.” They eventually used a device called the Colossus to quickly decrypt the transmissions.

This proved especially important ahead of D-Day, the museum says, “as the Allies knew Hitler had swallowed the bait story that landings would be at Calais.”

The museum recently received a Lorentz SZ42 machine (the device that does the actual encryption) on long-term loan from the Norwegian Armed Forces Museum.

The museum says it plans to “restore the machine to working order” but they’re missing a drive motor and are appealing for help finding one. Once it’s up and running, they’ll be able to “tell from beginning to end the tale of how the allies broke Germany’s secret codes,” the Guardian reported.

This is what it looks like, in case you happen to have one lying around!

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